Koheron LD101 is a 1550 nm, low-noise, DFB laser with integrated current driver, photodetector and RF modulation. It works on a single 3.3V power supply and is designed to be mounted on a standard M6 metric breadboard. Laser current is adjusted with a precision trimmer ranging from 0 to 55 mA. The LD101 features an AC-coupled modulation input for current modulation. The internal photodetector includes a transimpedance amplifier with a gain of 2 V/mA and 40 MHz bandwidth. The LD101 has a typical spectral linewidth of 5 MHz.
|Optical power (30 mA current)||3 mW|
|Spectral linewidth||5 MHz (typ.) / 8 MHz (max.)|
|Integrated optical isolation||30 dB|
|Fiber output||1 m SM fiber with FC/APC connector|
|Current monitoring gain||40 mV/mA|
|AC modulation cut-off frequency||1.6 kHz|
|Gain||20 mA/V above 100 kHz|
|Output impedance||50 Ω|
|Power supply||3.3 V - 5 V|
|I/O||SMA for modulation and internal photodetector|
|Outside dimensions (excl. fiber)||64 mm x 45 mm x 14 mm|
|Operating temperature||0 - 50 °C|
Relative intensity noise
We characterized the laser relative intensity noise (RIN) for different operating currents. In all measurements, the same optical power (1 mW) was sent to the photodetector to maintain the same shot-noise floor.
We measured the LD101 spectral linewidth using the self-homodyne method with a 10 km fiber delay. The figure below shows the power spectral density of the interference signal:
The graph below shows the frequency response of the AC-coupled modulation input at 40 mA current and 1 Vpp modulation.
Example: 100 kHz triangle
We modulated the laser current with a 100 kHz triangle wave. The graph below shows in yellow the modulation signal, in blue the monitoring output and in green the laser output observed with a PD100-DC photodetector.
Internal photodetector output
The graph below shows the frequency response of the internal photodetector output. Bandwidth at 3 dB is about 40 MHz.